ABSTRACT HEALTHY CLOSE RELATIONSHIPS (HCR) ? MOBILE Growing up in under-resourced environments (e.g., poverty, low-income, geographical isolation, fragile family structures) can seriously threaten an adolescent?s successful passage to adulthood. Researchers have uncovered very separate and unequal pathways to adulthood for adolescents?one for the ?haves?, one for the ?have-nots?, and a path for those who are in-between. The networks of close relationships of ?have-nots? are particularly important because of the extra challenges of growing up in under-resourced environments. The changing nature of these relationships may make it particularly challenging for many adolescents to establish and maintain healthy relationships; some adolescents may not feel very self-efficacious regarding their close relationships. Despite the importance of adolescents? network of relationships, our extensive search of healthy relationship programs and interventions revealed that no programs have simultaneously targeted relationships with parents, peers, and romantic partners. Moreover, the content of the existing programs focusing on one kind of relationship were rarely based on developmental theory and outcome measures were not closely linked to the program?s content. The goal of this Phase I project Healthy Close Relationships (HCR) ? Mobile is to determine the feasibility and merit of mobile game app that provides adolescents, ages 12-14 with the knowledge, skills and self-efficacy to engage in and manage healthy relationships with parents, peers, and romantic partners. We build upon on our two decades of work developing risk reduction interventions for adolescents and successfully developing a set of Edugames that focus on positive possible identities. To guide the content development and gaming process, the REESSI team will use Bandura?s Social Cognitive Theory for Health Promotion (2011) to select our change mechanism of promoting self- efficacy in relationships. The use of serious learning games to promote healthy relationships is a particularly promising step. Specifically, the Edugames provide a means of simulating interactions with someone without requiring that the other person actually be present, making this approach more feasible than other intervention approaches. Our overarching questions focus on (a) the end-users (children aged 12-14) in out-of-school time settings and the staff who run these programs and (b) the theorized process. Regarding the end- users, to what extent do they find the four prototype Edugames games to be usable and appealing? Regarding the theorized process, to what extent do children differ in their perceived capacity to maintain open communication with parents from pre-survey to post-survey? This Phase I application is guided by four specific aims. The Phase I aims over an eight-month period are: 1) With input from an established group of youth advisors, develop the curricula, plot arcs and game design document (GDD) for the prototypes of four Edugames; 2) Develop the web interface for the mobile game app; 3) Build the 10-minute prototypes for the four Edugames; 4) Conduct feasibility testing of the four prototype Edugames and associated off-line activities at four out-of-school time program sites. This project involves a trans-disciplinary collaboration between REESSI, one of the top adolescent development experts in the field (Dr. Wyndol Furman ? University of Denver), four youth- serving organizations and a premier globally recognized gaming company (zGames).